11HY017 Standard Meat Yield Tests in Turkey Processing

INFO SHEET
Standard Meat Yield
Tests in Turkey
Processing Plants
[email protected]
www.hybridturkeys.com
Standard Meat Yield Tests in Turkey Processing Plants
Introduction
Background
Carcass yield and part yield are the two most important
variables in a fully integrated turkey company. Even small
changes can significantly impact a company’s profit/loss
position (see Hybrid Info Sheet—Breast Meat Yield in
Commercial Turkeys: Utilizing the Genetic Resource). Much
time and capital are expended measuring carcass or part
yield, providing information to make management decisions.
The very nature of a highly efficient turkey processing
facility makes it extremely difficult to measure yield on the
production line with sufficient accuracy to evaluate even the
most influential factors.
Hahn & Spindler (2002) published a detailed Method of
Dissection of Turkey Carcasses, but the procedure is too
meticulous for use with large numbers of birds. Their report
describes exact cuts in precise detail but requires 12 to 15
minutes per bird to produce 25 pieces from a single carcass.
Currently, there is interest in a uniform meat yield test that
might facilitate the comparison of yield results between
plants and companies. The need for a standardized yield
evaluation may be justified in several ways within the global
turkey industry. When companies wish to compare yields
between plants or facilities they often find differences in
methodology or technique that add undesirable variation to
the data making it difficult to compare results from one
location to another. There is also a desire for some universal
bench marking resource that could receive data from plants
and provide anonymous comparisons between companies
or geographic locations.
In such a production environment, the proven method for
studying important, but highly variable traits is through the
use of a regimented statistical process control system (SPC).
SPC is a quality control concept incorporated into the Six
Sigma philosophy and is used for monitoring, controlling,
and improving a process through statistical analysis.
The four basic steps in any SPC system are:
1. Measure attributes of the process
2. Characterize/minimize the variance
Larger data sets from uniform yield tests may also add more
credibility and confidence to the yield information. This
discussion offers the basis for such a program by providing a
description for a universal method of separating a turkey
carcass for part weights and meat yield evaluation.
3. Track the process
4. Improve the process
Without a SPC system in place, many companies try to
improve by making random changes in their operations. The
danger here is that there is no benchmark or standard
against which the process can be compared and evaluated
for its effectiveness.
The intent of this article is to describe a simplified standard
measurement system for the collection of carcass and part
yield in turkey processing plants. By adopting such a
procedure, integrated turkey companies will more accurately
measure the two most important variables in their operation
and develop a knowledge base that will lead to better
management decisions.
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Standard Meat Yield Tests in Turkey Processing Plants
Scope
Boning Carcass Weight
The purpose of this yield evaluation is to compare the
muscle yield of carcasses on a routine basis. Although the
yield information may be used in a variety of ways, the
objective is to simulate production standards on the boning
line, not to obtain absolute perfection by scraping the
bones to remove every gram of muscle tissue. There may
be a need for an extensive evaluation occasionally but this
procedure is intended to simulate effective and efficient
boning yields. Consequently, it is recommended that this
evaluation be conducted away from the production line in
the processing plant (off line). Set aside an area within the
processing facility where the yield evaluation can take
place without interrupting critical work flow on the
production lines.
From a designated sample of birds, or
at random from the exit end of the
chiller, select the appropriate number
of carcasses for boning evaluation.
Only complete, wholesome carcasses
should be chosen eliminating the need
to estimate the weight of missing
carcass parts. Carcasses with skin
tears, trims or bruises should be
overlooked as well, since these usually
Fig. 1: Chilled Carcass
result in extra moisture loss or gain
during the chilling process adding more variation to the sum
of the boned parts.
It may be tempting to specify 25 cuts per carcass, to
generate marketable pieces. However, the process becomes
tedious and time consuming requiring 12 to 15 minutes per
bird (i.e. 4-5 birds/hr). Extensive boning also requires that
the designated personnel be proficient at each and every cut
to maintain uniformity in even the smaller pieces.
A much better approach has been to limit cuts to a
minimum meaningful number, extracting only those larger
pieces that hold economic value and thereby reducing the
number of cuts required. Holding the number of weighed
parts to 9 or 10 will also reduce the time necessary to cut up
each carcass. This allows one person to evaluate each bird in
3 to 4 minutes (15- 20 birds/hr).
Production staff, quality assurance and accounting
personnel should all agree on the information required
before a yield evaluation procedure can be established.
The ultimate goal with this yield evaluation is to generate
accurate numbers with which to make confident decisions
about processes, procedures, nutrition programs and
market age. Therefore, establishing a valid test that can
be conducted on a routine basis with confidence
and repeatability is crucial based upon the investment of
allocated resources.
Storing chilled carcasses for more than a few hours may also
alter the moisture content of sample carcasses. Chilled
carcasses may lose moisture to drip loss if held for an
extended period post chilling. Storage time should be a
factor in comparing yield of freshly chilled carcasses to the
yield of carcasses stored overnight then evaluated the next
day. Consideration is also required when comparing data
from air chilled versus water chilled carcasses. Water chilling
may increase carcass weight by as much as 6% while air
chilled carcasses may lose 1% of their total weight during
the process. Percent breast meat yield may appear lower on
water chilled carcasses since the initial carcass weight
increases by about 6% from added water. Actual breast
meat weight should not be affected.
Prior to obtaining an initial carcass weight, remove the neck,
if not removed before chilling. Remove excess water from
the cavity by holding the carcass, legs down, and shaking it.
It may also be positioned upright within the storage vat
prior to boning, allowing excess water to drain before
evaluation. The starting point of reference for this test
becomes a CWOG (chilled carcass without giblets, Fig. 1).
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Standard Meat Yield Tests in Turkey Processing Plants
Removing Parts
Orientation of the carcass for
boning may differ between plants,
or between the production line and
the designated boning station.
Some carcasses are held upright on
a cone positioned within the carcass
cavity such that the wings are on
top and the legs hanging down.
Other methods include hanging the
carcass from a shackle by the hocks
with the breast and wings extending
Fig. 2: Parts tub
downward. Either method is equally
precise but the position of the carcass usually dictates the
order that parts are removed.
The parts of each carcass to be
evaluated should be removed and
placed within a storage tub (Fig. 2).
Also include any identifying tag or
band, until the parts can be
weighed individually and recorded.
A tare weight should be obtained
for each tub prior to weighing to
expedite data recording.
Recording individual part weights
may be automated within some
facilities by connecting a PC to the scale (Fig. 3). The entire
procedure can be streamlined even more by inserting a load
cell and interfacing a computer with the boning apparatus.
Fig. 3: PC & Scale
This equipment makes it possible to retrieve data efficiently
during the removal of parts. It also eliminates the need to
stop and weigh parts on a separate scale and the need to
record data manually then enter the data into a computer by
hand. At least one such apparatus, the Standard Yield
Measurement System, is commercially available and
information is available online.
Cone Deboning
Place the drained carcass on the cone with the wings up and
the legs down. Remove any identification tag or band from
the carcass and place it in the tub that will hold the parts as
they are removed. Remember to obtain a tare weight for the
tub if it will be used to weigh parts.
Back Saddle
Some plants will remove the entire back saddle and bone it
separately on an adjacent table or simply weigh the back
saddle and return it to production
while concentrating solely on the
front saddle and white meat yield. If
parts of the back saddle are to be
evaluated, the tail may be removed
or omitted, leaving it attached to
the back.
Continue to separate the back
saddle, by removing the drums
(Fig. 4). First cut the skin between
Fig. 4: Drumstick
the ribs and the thigh, then
dislocate the thigh from the pelvis. Separate the drum from
the thigh and set the drum aside. Repeat this procedure for
the opposing leg.
In most instances, a weight for
boneless skinless thigh meat will not
be required. This simplifies the
process and accelerates the
procedure by allowing the whole
thigh to be removed intact. If a
measurement for boneless, skinless
thigh meat is required the following
process should be used. Score the
thigh skin on the back of the
carcass then remove the skin from
each thigh. Remove the femoral
bone from each thigh (Fig. 5) then
Fig. 5: Thigh bone
cut the thigh meat from the carcass
being careful to include all of the tensor and sartorius
muscles (dark oyster) from the dorsal side of the pelvis.
Repeat for the other side.
Finally, separate the pelvis and lower back from the front
saddle by scoring the muscles with a knife then lifting the
caudal end of the pelvis away from the cone to dislocate the
vertebra. Place the pelvis along with the other parts into a
tub for weighing. This step may also be considered optional
and can be omitted if separate weights for the back and
pelvis are not required, leaving the frame intact.
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Standard Meat Yield Tests in Turkey Processing Plants
Front Saddle
While the front half of the bird remains on the cone, remove
each wing and set it aside (Fig. 6). Next, score the breast
skin between the neck and wing socket then along each side
of the carcass near the ribs. Pull or cut the breast skin away
from the carcass and place it aside for weighing (Fig. 7).
Fig. 10: Weighing parts
Sum of the Parts
Using this procedure will provide weights for the following
list of parts:
Fig. 6: Wing
Fig. 7: Breast Skin
The breast lobes will be removed next, mimicking as closely
as possible, cuts on the production line in the plant. Remove
the major breast muscles (Fig. 8) exposing the tenderloins
that lie against the sternum. Now detach the connective
tendon at the large end of both tenderloins and pull or cut
these muscles away from the breast bone by pulling
downward (Fig 9).
1CWOG or Sum of the Parts
2Wings
3Breast Skin
4Boneless skinless breast meat
5 Tenderloins
6 Scapulas (optional)
7Thighs
8Drums
9 Frame
At times, special circumstances may require that additional
cuts or trims need to be performed allowing meat weighed
during this evaluation to re-enter the product flow within
first or second processing. Accommodating the production
staff by including these cuts will help streamline the
utilization of meat after the yield test.
Fig. 8: Breast Muscle
Fig. 9: Tenderloin
If the scapula is to be removed and weighed, it can be
removed from both sides of the back at this time. The
remaining frame including back, ribs, and sternum can be
weighed to provide the sum of all parts (Fig. 10) or
discarded and its weight estimated as the residual of the
original carcass weight.
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Standard Meat Yield Tests in Turkey Processing Plants
Shackle Deboning
Boning carcasses from a shackle
rather than a cone can be just as
efficient but requires that the
order of part removal be
rearranged to facilitate restraining
the carcass during the process
(Fig. 11). Establishing a standard
procedure and reviewing it on a
routine basis will enhance the
accuracy of the process by
Fig. 11: On a Shackle
ensuring repeatability between
tests performed on different days or by different people.
References
Hahn, G. and Spindler, M. (2002). Method of Dissection of Turkey
Carcasses. World’s Poultry Science Journal, Vol. 58, page 179-197.
Hybrid info sheet: Breast Meat Yield in Commercial Turkeys: Utilizing the
Genetic Resource.
Data Quality
As with any task, reviewing
procedures often and cross
training staff members can help
ensure the consistent and efficient
production of yield information.
Photographs or video clips of this
procedure are often beneficial for
personnel to review frequently
and make it easier to train new
employees when the need arises
Fig. 12: Photo record
(Fig. 12). Always remember that
many people rely on this yield information to make financial
decisions. Make every effort to generate good quality data,
check it often for accuracy and use it frequently to make
sound business decisions.
© Hybrid Turkeys
Unless otherwise specified, the information provided here is the property
of Hybrid Turkeys. Before reproducing or publishing this material in
any manner, please obtain approval by contacting the Hybrid Turkeys’
head office in Kitchener, Ontario, Canada.
[email protected]
www.hybridturkeys.com
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